1. Field of the Invention
The subject of the present invention is a device for thermal regulation of a circulating fluid, used especially to regulate the temperature of tooling or of reactors.
2. Description of the Prior Art
Such devices, intended to regulate the temperature of tooling for molding plastics, by means of a heat-transfer fluid circulating under the action of a pump already exist. In these devices, the temperature of the fluid can be increased by means of electrical heating resistance elements or decreased by means of second, cold fluid passing through an exchanger, the whole assembly being able to be controlled by means of an electronic regulator connected to one or more thermocouples judiciously arranged in the path of the heat-transfer fluid and by various safety devices.
In general, these devices include a heater-cooler of the heat-transfer fluid formed by a storage tank inside which is arranged an electrical heating resistance element and a cooling fluid circuit consisting of a coil, the electrical resistance elements being, of course, arranged inside an shielded tube, as described in document BF-A. 2,658,332 (VULCANIC SA).
In order to cool the heat-transfer fluid, other regulation devices include a plate exchanger. In these well-known exchangers, consisting of a stack of plates, the fluid to be cooled and the cold fluid circulate in two different circuits without contact with each other, on either side of each plate. The regulation devices, including such plate exchangers, are bulky since the heating resistance elements obviously have to be outside and some distance away from the said heat exchangers, whence the whole assembly forms a significant volume and has to have a large quantity of heat-transfer fluid circulating.
However, plate exchangers exist which include an electrical heating resistance element inserted between the plates, as described in Canadian Patent 979,059. These constructions do not make it possible to produce a thermoregulation device allowing the passage of several fluids which are to circulate vertically and alternately between the plates in order to emerge at the top and at the bottom of the device while at the same time being perfectly sealed.
In addition, with existing devices, a precise temperature with a very short response time cannot be obtained.